1. Field of the Invention
This invention relates to the field of windows having at least two panes of transparent material disposed therein, between which a fluid is inserted.
2. Prior Art
In the past, there have been disclosed reflective devices utilizing a transparent pane. U.S. Pat. No. 893,775--Saegmuller discloses a mirror for optical instruments, wherein a silvering material is applied to the back surface of a transparent plate. The back surface of a silvering material is polished and then covered by a second plate which may or may not be transparent. The silvering material cannot be removed unless this device is disassembled. U.S. Pat. No. 3,935,351--Franz discloses a multiple glazed glass article wherein one of the glass panels utilized is provided with two coatings, one being a metal and the other including a metal oxide. According to the inventor, the device provides useful and asthetic reflective and transmission properties. Again, the reflective material cannot be removed from the device without disassembling it. Again, in U.S. Pat. No. 3,999,345 there is disclosed an insulated building element comprising inner and outer spaced parallel sheets or plates of glass in which a thin film of reflective metal is applied to inner surface of the outer glass sheet. While it is disclosed therein that this reflective metal may be applied by the sputter-coating process, it may not be removed from the outer glass sheet without disassembling the device.
There has also been described in the past several items wherein at least two transparent panes have been held in juxtaposed position for the insertion of a liquid or vapor in the cavity therebetween. U.S. Pat. No. 2,441,831--Moore discloses a transparent double glazing unit having a chamber between the transparent panels into which is placed a transparent, electrically conductive medium consisting of a liquid into which an electrolyte has been dissolved. The function and purpose of this liquid is to heat the glass sheets substantially uniformly, thereby preventing clouding, frosting or icing thereof. U.S. Pat. No. 3,001,300--Green discloses a double glazed window which is capable of blocking vision on a percentage basis. There is a reservoir located between outer and inner transparent members into which a vapor is inserted. This vapor may comprise only air, in which case the device would be substantially transparent, or may consist of a colored fluid, the concentration of which is related to the percent of visibility.
There have also been disclosed devices which pass a liquid between substantially transparent panes such as U.S. Pat. No. 3,981,294--Deminet, et al. That reference discloses a glass composite building panel which is constructed of three layers of glass separated by integral raised walls which define either vacuum cells or a serpentine passageway for liquid flow therethrough. The primary purpose of this reference is as a solar heat collector. The cavities contained in that device are either empty or filled with a fluid, and it would not be possible to utilize this device if the passageways which contained the heat absorbing fluid were only partially full. It is briefly stated that panel can be used in essence as an integral shade if an opaque, metallic or colored liquid is pumped therethrough. U.S. Pat. No. 4,093,352 discloses a window having face-to-face panes defining a cavity therebetween which is adapted to be selectively flooded with a colored liquid. The window thereby is characterized by the provision of a supply manifold located between the panes.
None of the above-cited references disclose a window comprising a frame, at least two transparent panes, means for holding the panes in a juxtaposed position, defining a fluid-tight cavitity therebetween, fluid having substantially the same reflective index as mercury, and means for inserting and removing the fluid to and from the cavitity. Similarily, none of these references shows a plurally glazed window wherein at least two of the transparent members have portions held in juxtaposed position while the other portions of the transparent members are releasably contacting each other.